1. Technical Field
The disclosure generally relates to lenses, and more particularly to a lens having a substantially rectangular light pattern and an LED (light emitting diode) unit incorporating the lens.
2. Description of Related Art
Nowadays LEDs (light emitting diodes) are applied widely in various applications for illumination. The LED is a highly pointed light source. Thus, light directly emitted from the LED may form a small light spot. However, the small light spot can only illuminate a small area. In order to achieve a large illumination area, a large number of LEDs are required to be incorporated in a lamp, thereby resulting in a high cost of the lamp.
What is needed, therefore, is a lens and an LED unit using the lens which can address the limitations described.